1922.] Experiments with Phosphates and Slags. 



Table 2. — Botanical Composition of the TIay bx Weight 



at Martins IIearne. 

 Sample taken : 9th August, 1920. 



I'lot 2. Plot 3. Plot 4. 



Basic Slag. Q^fga Rock 



High Untreated, phosphate. 



Soluble. ^ 



percent. percent. percent. 



Clover 27-5 11-2 35-0 



Grasses 68-0 58-5 54-2 



Weeds 9-5 30 3 10-8 



Horndon.— Samples of hay from the plots at this centre 

 were taken in 1920 and a partial analysis was made. 



It was quite evident from the figures that the various basic 

 slags and rock phosphates bring about the same type of im- 

 provement, and there is nothing to choose between them in 

 their effectiveness in this respect. It is thus reasonable to 

 assume that the quality or feeding value of the hay produced 

 from each must be similar. 



Effect of Various Phosphates on the Pasture Herbage. — 

 It is not possible at Horndon to cut the plots for hay in suc- 

 cessive years. It is essential to alternate with grazing in order 

 to establish a close bottom which will in the succeeding year, 

 when the meadow is reserved for hay, protect the surface 

 from the direct rays of the sun, keep the soil cool and thereby 

 retain moisture and so enable the crop to grow. During 1919 

 the plots at Horndon were grazed by cattle and sheep. The 

 contrast between the various plots was so striking that at the 

 suggestion of Sir John Eussell an endeavour was made to deter- 

 mine the percentage of the ground space occupied by the various 

 species. In making the determination the method recom- 

 mended by Armstrong* was followed. The results are set 

 out in Table 3 and illustrated in Fig. 7. 



Four interesting points emerge from the results : — 



(1) The various basic phosphates, whether rock phosphates, 

 high or low soluble slags, or basic superphosphate (superphos- 

 phate and lime), bring about exactly the same t\"pe of improve- 

 ment in the pasture and they are equally effective in this 

 respect. 



(2) It is quite evident, if the results in Table 3 are compared 

 with the weights of hay in the same plots in the succeeding 

 year, that it is impossible to judge of the relative value of the 

 various phosphates as regards yields of hay by an inspection of 



* Journal of Agricultural Science, Vol. II, p. 283. 



